Definition: You are given a question on high school geography. You are also given 4 answer options (associated with "A", "B", "C", "D"), out of which only one is correct. You need to answer the question by selecting the correct option. You should only answer with the choice letter, not the whole answer.
Input: A city that is more than twice as large as the next largest city in a country is called a
(A)global city. (B)world leader city. (C)megalopolis. (D)primate city.

D